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Children, Adults gunned down in Connecticut school massacre

In one of the deadliest school shootings in U.S. history, a gunman opened fire Friday in a Connecticut elementary school, killing nearly 30 people — most of them children, a law enforcement official receiving information from the scene told CNN.

At least 10 of the dead at Sandy Hook Elementary School were students, a different law enforcement source familiar with the investigation said. Among the dead were the school’s principal and psychologist, according to a parent who was at the school when the incident happened.

At a news conference Friday afternoon, state police Lt. Paul Vance declined to put a number on the deaths. He would say only that there had been “several fatalities.” Police were waiting to notify families before releasing details, but he reassured nervous residents that the school was secure, the danger past.

President Barack Obama addressed the shooting in an emotional statement Friday afternoon, saying, “Our hearts our broken today.” Obama, a father to two girls, wiped away tears as he noted the nation has “endured too many of these tragedies in the past few years.”

Obama ordered flags to half-staff nationwide in tribute to the victims.

If the number of fatalities holds up, the Newtown shooting would be the second-deadliest school shooting in U.S. history, behind only the 2007 shooting at Virginia Tech that left 32 people dead.

The 1999 Columbine High shooting in Littleton, Colorado, is the deadliest at a U.S. elementary, junior or high school. In that incident, two students shot 13 people to death before killing themselves.